Penguin Facts: Species & Habitat Penguin Facts: Species & Habitat By Alina Bradford, Live Science Contributor | September 22, 2014 04:30pm ET MORE Credit: Dr. Robert Ricker, NOAA/NOS/ORR Penguins are torpedo-shaped, flightless birds that live in the southern regions of the Earth. Though many people imagine a small, black-and-white animal when they think of penguins, these birds actually come in a variety of sizes, and some are very colorful. For example, crested penguins sport a crown of yellow feathers. Blushes of orange and yellow mark the necks of emperor and king penguins. What look like bright yellow, bushy eyebrows adorn the heads of some species, such as the Fiordland, royal, Snares and rockhopper penguins. The macaroni penguin's name comes from the crest of yellow feathers on its head, which looks like the 18th-century hats of the same name. A light yellow mask covers the face of the yellow-eyed penguin around the eyes. An Adélie penguin on Penguin Island, which forms part of the South Shetland Islands of Antarctica.

Credit: Gemma Clucas According to the Integrated Taxonomic Information System (ITIS), there are 19 species of penguin. (Some experts, however, say the eastern rockhopper is a subspecies of the southern rockhopper.) [ Gallery: Photos of 18 Penguin Species ] The smallest penguin species is the little (also called little blue) penguin. These birds grow to 10 to 12 inches (25.4 to 30.48 centimeters) tall and weigh only 2 to 3 lbs. (0.90 to 1.36 kilograms). The largest penguin is the emperor penguin. It grows to 36 to 44 inches (91.44 to 111.76 cm) tall and weighs 60 to 90 lbs (27.21 to 40.82 kg). Where do penguins live? Considered marine birds, penguins live up to 80 percent of their lives in the ocean, according to the New England Aquarium . All penguins live in the Southern Hemisphere, though it is a common myth that they all live in Antarctica.

In fact, penguins can be found on every continent in the Southern Hemisphere. It is also a myth that penguins can only live in cold climates. The Galapagos penguin, for example, lives on tropical islands at the equator. What do penguins eat? Penguins are carnivores; they eat only meat. Their diet includes krill (tiny crustaceans), squid and fish. Some species of penguin can make a large dent in an area's food supply. For example, the breeding population of Adélie penguins (about 2,370,000 pairs) can consume up to 1.5 million metric tons (1.5 billion kg) of krill, 115,000 metric tons (115 million kg) of fish and 3,500 metric tons (3.5 million kg) of squid each year, according to Sea World . The yellow-eyed penguin is very tenacious when foraging for food. It will dive as deep as 120 meters (393.70 feet) up to 200 times a day looking for fish, according to the Yellow-Eyed Penguin Trust .

Mating & baby penguins A group of penguins is called a colony, according to the U.S. Geological Survey. During breeding season, penguins come ashore to form huge colonies called rookeries, according to Sea World. Most penguins are monogamous. This means that male and female pairs will mate exclusively with each other for the duration of mating season. In many cases, the male and female will continue to mate with each other for most of their lives. For example, research has found that chinstrap penguins re-paired with the same partner 82 percent of the time and gentoo penguins re-paired 90 percent of the time. At around three to eight years old, a penguin is mature enough to mate. Most species breed during the spring and summer. The male usually starts the mating ritual and will pick out a nice nesting site before he approaches a female. After mating, the female emperor or king penguin will lay a single egg. All other species of penguins lay two eggs. The two parents will take turns holding the eggs between their legs for warmth in a nest. The one exception is the emperor penguin .

The female of this species will place the egg on the male's feet to keep warm in his fat folds while she goes out and hunts for several weeks. When penguin chicks are ready to hatch, they use their beaks to break through the shell of their eggs. This process can take up to three days. After the chicks emerge, the parents will take turns feeding their offspring with regurgitated food. Penguin parents can identify their offspring by unique calls that the chick will make. Emperor penguins may migrate to find new nesting grounds. Credit: Michelle LaRue Penguins: aquatic, flightless birds found in the Southern Hemisphere Index of Penguin Species Most penguins feed on krill, fish, squid, and other forms of sealife caught while swimming underwater. They spend half of their life on land and half in the oceans. Penguins seem to have no special fear of humans and have approached groups of explorers without hesitation. This is probably on account of there being no land predators in Antarctica or the nearby offshore islands that prey on or attack penguins. Instead, penguins are at risk at sea from predators such as the leopard seal.

Typically, penguins do not approach closer than about 3 meters (9 feet); they become nervous at about that distance. This is also the distance that Antarctic tourists are told to keep from penguins (tourists are not supposed to approach closer than 3 meters, but are not expected to withdraw if the penguins come closer). Penguin biology Penguins are superbly adapted to an aquatic life. Their wings have become flippers, useless for flight in the air. In the water, however, penguins are astonishingly agile. Within the smooth plumage a layer of air is preserved, ensuring buoyancy. The air layer also helps insulate the birds in cold waters. On land, penguins use their tails and wings to maintain balance for their upright stance. All penguins are countershaded - that is, they have a white underside and a dark (mostly black) upperside. This is for camouflage. A predator looking up from below (such as an orca or a leopard seal) has difficulty distinguishing between a white penguin belly and the reflective water surface. The dark plumage on their backs camouflages them from above.

Diving penguins reach 6 to 12 km/h (3.7 to 7.5 mph), though there are reports of velocities of 27 km/h (17 mph) (which are more realistic in the case of startled flight). The small penguins do not usually dive deep; they catch their prey near the surface in dives that normally last only one or two minutes. Larger penguins can dive deep in case of need. Dives of the large Emperor Penguin have been recorded which reach a depth of 565 m (1870 ft) and last up to 22 minutes. Penguins either waddle on their feet or slide on their bellies across the snow, a movement called "tobogganing", which conserves energy while moving quickly. They also jump with both feet together if they want to move more quickly or cross steep or rocky terrain. Penguins have an average sense of hearing for birds (Wever et al 1969); this is used by parents and chicks to locate one another in crowded colonies (Jouventin et al 1999).

Their eyes are adapted for underwater vision, and are their primary means of locating prey and avoiding predators; in air it has been suggested that they are nearsighted, although research has not supported this hypothesis (Sivak et al 1987). Penguins have a thick layer of insulating feathers which are designed to keep them warm in water (heat loss in water is much greater than in air). The Emperor penguin (the largest penguin) has the largest body mass of all penguins, which further reduces relative surface area and heat loss. They also are able to control blood flow to their extremities, reducing the amount of blood which gets cold, but still keeping the extremities from freezing. In the extreme cold of the Antarctic winter, the females are at sea fishing for food leaving the males to brave the weather by themselves. They often huddle together to keep warm and rotate positions to make sure that each penguin gets a turn in the center of the heat pack. They can drink salt water because their supraorbital gland filters excess salt from the bloodstream. The salt is excreted in a concentrated fluid from the nasal passages. Breeding Some penguins mate for life, others for just one season.

They generally raise a small brood, and the parents cooperate in caring for the clutch and the young. During the cold season on the other hand the mates separate for several months to protect the egg. Usually, the male stays with the egg and keeps it warm while the female goes to sea to find food for the baby. When the female comes back, they switch roles. When mothers lose a chick, they sometimes attempt to "steal" another mother's chick, usually unsuccessfully as other females in the vicinity assist the defending mother in keeping her chick. In some species, such as Emperor Penguins , young penguins assemble in large groups called crèches. Isabelline Penguins Perhaps one in 50,000 penguins (of most species) are born with brown rather than black plumage. These are called Isabelline penguins, possibly in reference to the legend that the archduchess Isabella of Austria vowed not to change her undergarments until her husband united the northern and southern Low Countries by taking the city of Ostend--which took three years to accomplish. Isabellinism is different from albinism, though the faded color of the plumage calls albinism to mind.

Isabelline penguins tend to live shorter lives than normal penguins, as they are not well camouflaged against the deep, and are often passed over as mates. Systematics Updated after Marples (1962), Acosta Hospitaleche (2004), and Ksepka et al. (2006). See the gallery for images of most living species. ORDER SPHENISCIFORMES Basal and unresolved taxa (all fossil) Waimanu - basal (Middle-Late Paleocene): Waimanu was a genus of early penguin which lived soon after the Cretaceous-Tertiary extinction event, lending support to the theory that the radiation of modern birds took place before the extinction of the dinosaurs, not after as others had proposed. While it was a very early member of the sphenisciformes, Waimanu was flightless (like all modern members of its order). Though its wing bones do not show the extreme specializations modern penguins have for an aquatic lifestyle, it does seem adapted for wing-propelled diving, and may have resembled a flightless loon.

Discovered in Canterbury, New Zealand riverbed sediments (near the Waipara River) of the Waipara Greensand Formation in 1980, the name Waimanu comes from Māori for "waterbird". Two species are known, W. manneringi from the Early Paleocene and W. tuatahi from the Late Paleocene.Perudyptes (Middle Eocene of Atacama Desert, Peru) - basal?Sphenisciformes gen. et sp. indet. CADIC P 21 (Leticia Middle Eocene of Punta Torcida, Argentina: Clarke et al. 2003)Delphinornis (Middle/Late Eocene ?- Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Archaeospheniscus (Middle/Late Eocene - Late Oligocene) - Palaeeudyptinae? New subfamily 2? : Archaeospheniscus is an extinct genus of large penguins. It currently contains three species, known from somewhat fragmentary remains. A.

wimani, the smallest species (about the size of a Gentoo Penguin ), was found in Middle or Late Eocene strata (34-50 MYA) of the La Meseta Formation on Seymour Island, Antarctica, whereas the other two, about the size of a modern Emperor Penguin , are known from bones recovered from the Late Oligocene Kokoamu Greensand Formation (27-28 MYA) at Duntroon, New Zealand . The genus is one of the earliest known primitive penguins. Its humerus is still very slender, between the form seen in ordinary bird wings and the thickened condition found in modern penguins. On the other hand, the tarsometatarsus shows a peculiar mix of characters found in modern and primitive forms. Whether this signifies that the genus is an ancestor of modern taxa or represents a case of parallel evolution is unknown. Species Lowe's Penguin (Archaeospheniscus lowei) : Lowe's Penguin (Archaeospheniscus lowei) is the type species of the extinct penguin genus Archaeospheniscus. It stood approximately 85-115 cm high, between a modern King Penguin and an Emperor Penguin in size.

It is known from bones of a single individual (Otago Museum C.47.20) and possibly some additional material such as the OM C.47.27 femur, all recovered from the Late Oligocene Kokoamu Greensand Formation (27-28 MYA) at Duntroon, New Zealand . The species' binomen was given in honor of Percy Lowe, who researched prehistoric penguins and proposed a theory (now considered erroneous) that these birds were derived from reptiles independently of the other modern birds. Lopdell's Penguin (Archaeospheniscus lopdelli) : Lopdell's Penguin (Archaeospheniscus lopdelli) was the largest species of the extinct penguin genus Archaeospheniscus, standing about 90-120 cm high, or somewhat less than the extant Emperor Penguin . It is only known from bones of a single individual (Otago Museum C.47.21) which was found in the Late Oligocene Kokoamu Greensand Formation (27-28 MYA) at Duntroon, New Zealand .

Bones apparently belonging to this species are now also known from the Late Eocene La Meseta Formation (34-37 MYA) on Seymour Island, Antarctica (Tambussi et al., 2006). As the bird is not very well distinguished except in size from its contemporary congener Archaeospheniscus lowei and the size range, an estimated 85-120 cm, is in the upper range of the variation found in modern penguins, it is probable that A. lopdelli is a synonym of A. lowelli. As the recent finds in Antarctica suggest, this is far from certain, however, and there remains much to be learned about the systematics and biogeography of the two larger Archaeospheniscus species. The species' binomen honors J. C. Lopdell, who assisted Marples in recovering the fossils of this bird and others found in the Duntroon excavations. Archaeospheniscus wimani : Archaeospheniscus wimani is an extinct species of penguin.

It was the smallest species of the genus Archaeospheniscus, being approximately 75-85 cm high, or about the size of a Gentoo Penguin . It is also the oldest known species of its genus, as its remains were found in Middle or Late Eocene strata (34-50 MYA) of the La Meseta Formation on Seymour Island, Antarctica. It is known from a fair number of bones. The species' binomen honors Carl Wiman, an early 20th century researcher who laid the groundwork for the classification of the prehistoric penguins. Marambiornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1?Mesetaornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1?Tonniornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica)Wimanornis (Late Eocene -?

Early Oligocene of Seymour Island, Antarctica)Duntroonornis (Late Oligocene of Otago, New Zealand ) - possibly SpheniscinaeKorora (Late Oligocene of S Canterbury, New Zealand )Platydyptes (Late Oligocene of New Zealand ) - possibly not monophyletic; Palaeeudyptinae, Paraptenodytinae or new subfamily?Spheniscidae gen. et sp. indet (Late Oligocene/Early Miocene of Hakataramea, New Zealand )Madrynornis (Puerto Madryn Late Miocene of Argentina) - possibly Spheniscinae Pseudaptenodytes (Late Miocene/Early Pliocene) : The extinct penguin genus Pseudaptenodytes contains the type species P. macraei; smaller bones have been assigned to P. minor, although it is not certain whether they are really from a different species or simply of younger individuals; both taxa are known by an insufficient selection of bones.

The fossils of Pseudaptenodytes have been found in deposits in Victoria ( Australia ) which are of Late Miocene or Early Pliocene age.Dege (Early Pliocene of South Africa) - possibly SpheniscinaeMarplesornis (Early Pliocene) - possibly SpheniscinaeNucleornis (Early Pliocene of Duinfontain, South Africa) - possibly Spheniscinae Inguza (Late Pliocene) - probably Spheniscinae; formerly Spheniscus predemersus : Inguza predemersus is an extinct species of penguin. It was formerly placed in the genus Spheniscus and presumed to be a close relative of the African Penguin , but after its well-distinct tarsometatarsus was found, it was moved into its present monotypic genus (a genus consisting of only one species). What is known from molecular data is that the time at which the present species lived is not too distant from the arrival of the ancestors of the African Penguin on the Atlantic coasts of southern Africa. On the other hand, it may be closer to Pygoscelis .

This would mean that its ancestors diverged from those of the extant Pygoscelis most likely at an indeterminate point of time during the Oligocene.(Baker et al. 2006) Alternatively, it might not be close to extant penguins (the Spheniscinae), but a late survivor of an extant lineage. This is not very likely given its age - it would be the last known survivor of the non-spheniscine penguins - but as some of these still lived a few million years ago, it cannot be ruled out. Family Spheniscidae Subfamily Palaeeudyptinae - Giant penguins (fossil): The New Zealand Giant Penguins, Palaeeudyptinae, are an extinct subfamily of penguins. It includes several genera of medium-sized to very large species - including Palaeeudyptes marplesi and Anthropornis nordenskjoeldi which grew 1.5 meters (4 ft 11.1 in) tall or even larger, and the massive Pachydyptes ponderosus which weighed at least as much as an adult human male. They belonged to an evolutionary lineage more primitive than modern penguins.

In some taxa at least, the wing, while already having lost the avian feathering, had not yet transformed into the semi-rigid flipper found in modern penguin species: While the ulna and the radius were already flattened to increase propelling capacity, the elbow and wrist joints still retained a higher degree of flexibility than the more rigidly lockable structure found in modern genera. The decline and eventual disappearance of this subfamily seems to be connected by increased competition as mammal groups such as cetaceans and pinnipeds became better-adapted to a marine lifestyle in the Oligocene and Miocene. The members of this subfamily are known from fossils found in New Zealand , Antarctica, and possibly Australia, dating from the Middle or Late Eocene to the Late Oligocene; the Australian Middle Miocene genus Anthropodyptes is also often assigned to this subfamily, as are the remaining genera of primitive penguins except those from Patagonia. Indeed, it was long assumed that all prehistoric penguins which cannot be assigned to extant genera belonged into the Palaeeudyptinae; this view is generally considered obsolete today.

It is likely that some of the unassigned New Zealand / Antarctican/ Australian genera like Delphinornis, Marambiornis, and Mesetaornis do indeed belong into this subfamily, but it is just as probable that others, such as Duntroonornis and Korora, represent another, smaller and possibly somewhat more advanced lineage. The Palaeeudyptinae as originally defined (Simpson, 1946) contained only the namesake genus, the remainder being placed in the Anthropornithidae. The arrangement followed here is based on the review of Marples (1962) who synonymized the two, with updates to incorporate more current findings.

Crossvallia (Cross Valley Late Paleocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily Anthropornis (Middle Eocene ?- Early Oligocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily Nordenskjoeld's Giant Penguin, Anthropornis nordenskjoeldi : Anthropornis nordenskjoeldi, or Nordenskjoeld's Giant Penguin, was a penguin species that lived 45–37 million years ago, during the Late Eocene and the earliest part of the Oligocene. It reached 1.7 meters (5 ft 6.9 in) in height and 90 kilograms (198 lb) in weight. Fossils of it have been found on Seymour Island off the coast of Antarctica and in New Zealand . By comparison, the largest modern penguin species, the Emperor Penguin , is just 1.2 meters (3 ft 11.2 in) tall. Anthropornis nordenskjoeldi had a bent joint in the wing; this indicates a carryover from its flying ancestors.

Penguins were descended from grebe or loon-like ancestors, and became flightless as they became full-time swimmers. Icadyptes (Late Eocene of Atacama Desert, Peru) : Icadyptes salasi was a giant penguin species from the late Eocene period, in the tropics of South America. "Ica" for the Peruvian region where it was found, "dyptes" from the Greek word for diver, and "salasi" for Rodolfo Salas, a noted Peruvian paleontologist. The fossilised remains of the penguin, which lived some 36 million years ago, were found in the coastal desert of Peru by the team of North Carolina State University palaeontologist Dr. Julia Clarke, assistant professor of marine, earth and atmospheric sciences. Its well-preserved fossil skeleton was found on the southern coast of Peru together with an early Eocene species Perudyptes devriesi (comparable in size to the living King penguin ), and the remains of three other previously undescribed penguin species, all of which seem to have preferred the tropics over colder latitudes.

Perudyptes devriesi is named after the country, and Thomas DeVries, a University of Washington palaeontologist who has long worked in Peru. Standing 1.5 metres (5 ft) tall, the penguin was much larger than any of its modern-day cousins. It had an exceptionally long spear-like beak resembling that of a heron. The researchers who discovered the penguins believe the long, pointed beaks to be the likely ancestral shape for all penguins. Icadyptes salasi is the third largest penguin ever described. Icadyptes salasi and Perudyptes devriesi appear to have flourished at warmer latitudes at a time when world temperatures were at their warmest over the past 65 million years. Only a few modern-day penguins, such as the African and Galapagos penguins prefer such a balmy climate. The discovery of the fossils has caused a re-evaluation of penguin evolution and expansion. Previously, scientists believed that penguins evolved near the poles in Antarctica and New Zealand , and moved closer to the equator around 10 million years ago.

Since Icadyptes salasi lived in Peru during a period of great warmth, penguins must have adapted to warm-climates around 30 million years earlier than previously believed. Palaeeudyptes (Middle/Late Eocene - Late Oligocene) - polyphyletic (derived from more than one ancestral type); some belong in other subfamilies : Palaeeudyptes is an extinct genus of large penguins, currently containing four accepted species. They were probably larger than almost all living penguins, with the smaller species being about the size of an Emperor Penguin and the largest ones having stood about 1.5 meters tall. Of the four species, two (P. gunnari and P. klekowskii) are known from numerous remains found in Middle or Late Eocene strata (34 to 50 MYA) of the La Meseta Formation on Seymour Island, Antarctica. P.

antarcticus, the first fossil penguin described, is only really known from a single incomplete tarsometatarsus found in the Late Oligocene Otekaike Limestone (23 to 28, possibly up to 34 MYA) at Kakanui, New Zealand , but numerous other bones have been tentatively assigned to the species. The other described New Zealand species, P. marplesi, is known from parts of a skeleton, mainly leg bones, from the Middle or Late Eocene Burnside Mudstone (34 to 40 MYA) at Burnside, Dunedin. To this species also a number of additional remains have been tentatively assigned. The problem with the indeterminate New Zealand specimens is that they at least in part are intermediate in size between the two species (Simpson, 1971). It may be that P. marplesi simply evolved into the smaller P. antarcticus. Bones unassignable to species also were found on Seymour Island, but in these cases they seem to be from juvenile individuals or are simply too damaged to be of diagnostic value (Jadwiszczak, 2006).

In addition, an incomplete right tibiotarsus (long leg bone) (South Australian Museum P10862) and one left humerus (South Australian Museum P7158) and assignable to this genus were found in the Late Eocene Blanche Point Marls at Witton Bluff near Adelaide, Australia (Simpson, 1946, 1971). The supposed genus Wimanornis, based on two Seymour Island humeri, is apparently a synonym of P. gunnari (Jadwiszcak, 2006). The genus is the namesake for the subfamily of primitive penguins, Palaeeudyptinae. Altogether, their osteological characteristics seem to have been somewhat less advanced that those of the slightly smaller Archaeospheniscus and about on par with the gigantic Anthropornis. The exact nature of the relationship of the Palaeeudyptinae to modern penguins is unknown. Pachydyptes (Late Eocene) : Pachydyptes is an extinct genus of penguin. It contains the single species Pachydyptes ponderosus, the New Zealand Giant Penguin.

This taxon is known from a few bones from Late Eocene (34 to 37 MYA) rocks in the area of Otago, and a fine specimen found near Kawhia, New Zealand , in January 2006[verification needed]. With a height of 140 to 160 cm (about 5 ft) and weighing around 80 to possibly over 100 kg, it was the second-tallest penguin ever, surpassed only by Anthropornis nordenskjoeldi in size, but probably not in weight. As George Gaylord Simpson famously quipped, "Pachydyptes' height would not suffice for basketball but their weight was about right for American football." Pachydyptes was slightly larger than Icadyptes salasi, the best-identified of the giant penguins. Anthropodyptes (Middle Miocene) - tentatively assigned to this subfamily : Anthropodyptes is a poorly known monotypic (one single species) genus of extinct penguin. It contains the single species Anthropodyptes gilli, known from a Middle Miocene humerus from Australia.

The bone is somewhat similar to those found in members of the New Zealand genus Archaeospheniscus and thus this genus might, like them, belong to the subfamily Palaeeudyptinae. [edit] References Subfamily Paraptenodytinae - Stout-legged penguins (fossil) Arthrodytes (San Julian Late Eocene/Early Oligocene - Patagonia Early Miocene of Patagonia, Argentina) Paraptenodytes (Early - Late Miocene/Early Pliocene) : Paraptenodytes is an extinct genus of penguins which contains two or three species sized between a Magellanic Penguin and a small Emperor Penguin (P. antarcticus). They are known from fossil bones ranging from a partial skeleton and some additional material in the case of P. antarcticus, and a single humerus in the case of P. brodkorbi. The latter species is therefore often considered invalid; Bertelli et al. (2006) think that it is indeed valid, but distinct enough not to belong into Paraptenodytes.

The fossils were found in the Santa Cruz and Chubut Provinces of Patagonia, Argentina, in Patagonian Molasse Formation rocks of Early Miocene age; later occurrences are apparently from Late Miocene or possibly even Early Pliocene deposits (Stucchi et al. 2003). Together with the related genus Arthrodytes, they form the subfamily Paraptenodytinae, which is not an ancestor of modern penguins (Bertelli et al., 2006 Subfamily Palaeospheniscinae - Slender-legged penguins (fossil): Palaeospheniscus is an extinct genus of penguins which contains three species at present. They are all (except P. bergi, which is somewhat enigmatic) known from one or two handful of bones. All specimens were found in Santa Cruz and Chubut Provinces of Patagonia, Argentina. The fossils were recovered from the Patagonian Molasse Formation, and are probably Early Miocene to Late Miocene or possibly Early Pliocene in age (Stucchi et al. 2003).

Palaeospheniscus gracilis was long believed to be from the Early Oligocene, but this is now thought to be erroneous. P. gracilis and P. wimani are often considered synonyms of P. patagonicus[citation needed]. Recent researchers also tend to merge Chubutodyptes into this genus as P. biloculatus[citation needed]. The species of Palaeospheniscus were medium-sized to largish penguins, ranging from P. gracilis with an estimated maximal length of 55 cm to P. wimani, which reached up to 73 cm. Palaeospheniscus is the namesake genus of the subfamily Palaeospheniscinae, the Patagonian slender-legged penguins. These are apparently not closely related to the modern genus Spheniscus . Eretiscus (Patagonia Early Miocene of Patagonia, Argentina) Palaeospheniscus (Early? - Late Miocene/Early Pliocene) - includes Chubutodyptes : Palaeospheniscus is an extinct genus of penguins which contains three species at present. They are all (except P.

bergi, which is somewhat enigmatic) known from one or two handful of bones. All specimens were found in Santa Cruz and Chubut Provinces of Patagonia, Argentina. The fossils were recovered from the Patagonian Molasse Formation, and are probably Early Miocene to Late Miocene or possibly Early Pliocene in age (Stucchi et al. 2003). Palaeospheniscus gracilis was long believed to be from the Early Oligocene, but this is now thought to be erroneous. P. gracilis and P. wimani are often considered synonyms of P. patagonicus[citation needed]. Recent researchers also tend to merge Chubutodyptes into this genus as P. biloculatus[citation needed]. The species of Palaeospheniscus were medium-sized to largish penguins, ranging from P. gracilis with an estimated maximal length of 55 cm to P. wimani, which reached up to 73 cm. Palaeospheniscus is the namesake genus of the subfamily Palaeospheniscinae, the Patagonian slender-legged penguins.

These are apparently not closely related to the modern genus Spheniscus. Subfamily Spheniscinae - Modern penguins Aptenodytes - Great penguins (2 species) : The genus Aptenodytes (from the Greek for "flightless diver") contains two extant species of penguins collectively known as "the great penguins". PENGUINS - Habitat & Distribution Habitat & Distribution InfoBook Home Distribution All 18 species of penguins live in the Southern Hemisphere. (See Appendix for information on distribution for each species.) Penguins are found on every continent in the Southern Hemisphere. They are abundant on many temperate and subantarctic islands. In general, flightless penguins have greater limits on foraging ranges and search capacities compared to birds that can fly. Thus to be successful, penguins must find predictable food sources within their limited foraging range. The more northernly Spheniscus penguin species, for example, are limited in distribution to primarily highly productive areas of the ocean such as upswellings and continental shelves.

About 95% of Galápagos penguins, the most northernly of all penguin species, is found along the western coast of Isabela and around Fernandina Island by the most productive upswellings caused by the Equatorial Undercurrent (also called the Cromwell Current.) Habitat Penguins generally live on islands and remote continental regions free from land predators, where their inability to fly is not detrimental to their survival. These highly specialized marine birds are adapted to living at sea—some species spend months at a time at sea. Penguins are usually found near nutrient-rich, cold-water currents that provide an abundant supply of food. Different species thrive in varying climates, ranging from Galápagos penguins on tropical islands at the equator to emperor penguins restricted to the pack ice and waters of Antarctica. The seasons of the Southern Hemisphere are opposite those of the Northern Hemisphere. When continents above the equator experience spring and summer, the areas below the equator experience fall and winter. The most southerly penguin colony in the world are a group of Adélies that regularly nest near Camp Royds, Antarctica. Migration Adult penguins of most species usually disperse from rookeries (nesting colonies) to feed in coastal waters.

Adélie penguins in the southernmost breeding colonies in the Ross Sea migrate as much as 17,600 km (10,936 mi.) each year. Young birds usually disperse when they leave their colonies and may wander thousands of kilometers. They generally return to the colonies where they were hatched to molt and breed. Population data usually are gathered during the breeding season. Population Population data usually are gathered during the breeding season. Some researchers count chicks to estimate the total population, others count breeding pairs. (See Appendix for information on population estimates for each species.) Penguins Knowledge Base > Animals > Animals Penguins Penguins are a group of aquatic, flightless birds living almost exclusively in the southern hemisphere, especially in Antarctica. Student majoring in Business-Marketing Curated Facts The penguin species with the highest population is the Macaroni penguin with 11,654,000 pairs. The species with the lowest population is the endangered Galapagos penguin with between 6,000-15,000 individuals. Article: Basic Facts About Penguin... When in the water, penguins may be eaten by leopard seals, fur seals, sea lions, sharks, or killer whales.

On land, foxes, snakes, and introduced predators such as feral dogs, cats, and stoats (members of the weasel family) prey on eggs and chicks of some penguin species, including the yellow-eyed and Galapagos penguins. Article: Penguins Both parents take turns incubating the egg. The incubation period lasts from 4 weeks (Erect-Crested penguins) to 66 days (Emperor penguins). Chicks first occur by poking a small hole in the egg and they require attentive parents for survival. Once a chick has fledged, it is able to swim and becomes independent of its parents. Article: Penguin Reproduction Penguins stand upright while incubating a single egg on the tops of their feet under a loose fold of abdominal skin. Under this loose fold is a featherless patch of skin called a brood patch, which occurs in all incubating birds. The brood patch contains numerous blood vessels, that, when engorged with blood, transfer body heat to the eggs. Article: Original text There are some great qualities of penguins found in their reproduction process. They can mature for reproduction from about 4 to 8 years of age.

Generally the smaller species of penguins will mature at a younger age than the larger ones. However, the smaller ones also seem to have a life span that is much shorter. A number of species only mate with the same partner year after year. Article: Penguin Reproduction Penguins are among the most social of all birds. All species are colonial. Penguins usually associate in small groups while at sea, but often gather by the thousands when nesting on land. Penguins are among the most social of all birds. Penguins may swim and feed in groups, but some may be solitary when diving for food. Emperor penguins have been observed feeding in groups with coordinated diving. During the breeding season penguins come ashore and nest in huge colonies called rookeries. Some rookeries include hundreds of thousands of penguins and cover hundreds of square kilometers. Article: PENGUINS - Behavior Only a few penguins live in the warmer parts of the southern oceans. The Galapagos Penguin, breeding in the Galapagos region, may even breed a little north of the equator, and the Jackass Penguin (or African Penguin) may range as far north as the equator.

These penguins have special ways of keeping cool and live in places where cold ocean currents cool the immediate environment—the Humboldt Current in the eastern Pacific, and the Benguela and Agulhas Currents off South Africa. They are non-migratory species, so they’re not likely to stray too far north. Most other species never come further north than 45°S latitude. Specially adapted for life in cold places, they don’t wander into warm water. Article: North Pole Penguin A penguin’s diet can range from small fish to shrimps, small crayfish, barnacles and many other small shellfish. A penguin’s beak is very tough so it can remove the barnacles from the rocky surface of the sea bed. The penguin’s speed is fast enough to catch small fish swimming at their top speed along with other foods they like. Many penguins spend days out at sea eating many of their favourite foods, so that when they return to their colony they will be able to feed their young and their mate. Their mate would have spent the last few days caring for their younger penguins as they cannot fish for their own food yet.

The penguin that has been out at sea regurgitates the food for their partner and children to eat. Article: Blue Penguins Diet Penguins - PdfSR.com Penguins Penguins are flightless sea birds of the Southern Hemisphere. Worldwide there are 17 species of penguins, found in Antarctica, South Australia, New Zealand, and off the coasts of Peru, Chile, and South Africa. Some species live as far north as the equatorial Galapagos Islands, but penguins are primarily cold-weather birds. There are seven species of Antarctic penguins: the Adelie, Gentoo, Macaroni, Chinstrap, Rockhopper, King, and Emperor. The Adelie, Emperor, Chinstrap, and Gentoo penguins are the only four penguins that breed on the Antarctic continent. Physiology Penguins have a heavier skeleton than most birds, oily waterproof feathers, and specialized glands that extract and excrete excess salt. Their feathers, which even cover their bills and feet, combine with a thick layer of fat to insulate them. This works so effectively that the birds frequently overheat in the frigid waters.

Their size varies by species, from the sixteen inch, two and a half pound Little Blue penguin of Australia to the truly Antarctic sixty-six pound Emperor penguin, which stands more than three and a half feet tall. Penguins swim like other birds fly. Their wings have not disappeared, nor have they become vestigial, useless appendages. Instead, they've evolved into flippers. When underwater penguins use highly developed muscles to flap their wings to move forward, and they guide themselves with their tail. They are the only bird to "porpoise." Meaning, they launch themselves out of the water, momentarily flying in fluid arches as they continue to swim forward at high speeds like dolphins. Gentoo penguins are thought to be the fastest of all swimming birds, achieving speeds of thirteen to seventeen miles per hour. The Hunter and the Hunted Penguin’s predators include: leopard seals, sea lions, and killer whales. Skua gulls are the greatest natural threat to chicks and eggs. In turn, penguins dive to hunt fish, squid and krill -- a small shrimp-like crustacean.

Penguins’ dependence on krill was demonstrated in dramatic fashion in 1995, when thousands of Adelie and Emperor chicks died due to unusual movements of krill swarms. While hunting most penguins only submerge for about 1 minute, but Emperors can dive as deep as 180 feet for up to 18 minutes. Species Characteristics The Macaroni and Rockhopper penguins are in the same genus, Eudyptes. Both have yellow crests decorating and distinguishing their heads. In fact, the Macaroni gets its name for this feature after "Macaroni Dandies," resplendently dressed eighteenth century Englishmen. Some Macaronis breed on the Antarctic Peninsula. The five and a half pound Rockhopper is the smallest Antarctic species, but it compensates for its smallness by being the most aggressive of all penguins. The Gentoo, Chinstraps, and Adelies are the southernmost representatives of the genus Pygoscelis. These three species are roughly the same size.

The Gentoo is the rarest of the three, with a population of about 350,000 and is mostly found on South Georgia, an island northeast of the peninsula. The Chinstrap gets its name from markings on its head and neck, and it is considerably more abundant, at about ten million. Some Chinstrap penguins breed on the Antarctic Peninsula. The Adelie is the most numerous of the Antarctic penguins. Adelie penguins have the classic penguin look, being white and black with no adornments. On average, an Adelie weighs about 11 pounds and stands a little less than thirty inches tall. The Adelie breeds widely on the continent proper and its colonies can number in the millions. The Emperor and the King penguins belong to the genus Aptenodytes and look more alike than different. However, the Emperor is considerably larger, weighing twice as much on average. They both have yellow and orange markings around the neck, black heads, white bellies, and blue-gray backs. The King penguin breeds on the subantarctic islands, while the Emperor breeds on the continent's ice. The Emperor is the only bird that will live its entire life on ice.

Colonies Penguins breed in colonies and can be fiercely territorial. They breed closely together mostly because there is very little ice-free space. But they are also highly social animals that recognize individuals and return as adults to the rookery where they were born. The colony helps these birds guard, protect, and defend their young. Within these colonies, penguins build rookeries with pebbles and guano. The one exception to this is the Emperor penguin who does not build a nest at all because it breeds on the ice. Breeding Six of the seven Antarctic species breed during the summer; the Emperor breeds during the unbelievably cold, dark Antarctic winter. The Emperor has a longer gestation period than other penguins, so it must time its cycle in order to ensure its chicks become independent during the summer when food is abundant. Once the female lays the egg she leaves for two months to hunt and feed in the sea. The male is left behind to incubate the egg, which requires a two to three month fast that results in the male loosing from a third to half of his body weight. Upon hatching the female returns to rear the chick and the male ventures out to sea to regain his weight.

Threats Today, penguins are economically important in South America and South Africa for their guano, used for fertilizer, and as tourist attractions. In the past, commercial egg collecting caused severe damage to rookeries. Around the turn of the century, penguins were also slaughtered for their blubber -- especially the King. However, present day Antarctic penguins find their greatest human threats from inadvertent interference. Direct Threats Nearly all of Antarctica is covered in ice, this results in a competition for breeding areas among different breeding groups. This competition is intensified when humans begin utilizing the same ice-free areas. Tourism and airstrips on the continent can affect penguins in unpredictable and dangerous ways. Unfortunate incidents, like the building of the French airstrip Dumont d'Urville on the rocky Adelie coastline, have ruined some of the best bird breeding areas on the continent. (In 1994, a tidal wave washed away a good deal of that airstrip.) Indirect Threats Penguins are also threatened by the over-fishing of their main food source, krill.

Krill are considered a keystone species, meaning that they form a base upon which an entire ecosystem is dependent, conversely, if the krill stocks are depleted the effects are seen through the entire ecosystem, including penguins. There have also been discussions regarding the impact of climate change on krill abundance. While the global average temperature has increased by an average of .6°C it has increased in Antarctica peninsula by 2.5° C in the last 50 years. This rise in temperature is behind the decreasing sea-ice cover, which decreases the amount of algae which krill feed upon, thus reducing their abundance. With increasing awareness of climate change and its effects on melting ice, ocean currents, and overall temperatures, there are some scientists who are concerned that penguins will be especially hard hit by climate change. Scientists have now begun to explore the possibility that climate change is responsible for the population decline of the Adelie penguin by 33% over the last twenty years.

Protection Penguins are protected under the Antarctic Treaty System, the Agreed Measures for the Conservation of Antarctic Fauna and Flora (Recommendations III-8 of 1964), which prohibits killing, wounding, capturing, or molesting any native mammal or bird in Antarctica without a permit. Also governed by the Convention on the Conservation of Antarctic Marine Living Resources, which is part of the Antarctic Treaty System. The Convention takes a unique approach by managing from a complete ecosystem perspective and with a precautionary approach. Therefore decisions are made based on the health and wellbeing of the entire ecosystem and aimed a preventing damage instead of reacting to an already present situation. 1630 Connecticut Ave. N.W., 3rd Floor Washington, D.C. 20009-1053 theNAT | Flightless auk Flightless auk Coastal southern California; Rancho La Brea, Baja California In Our Region: Found in the San Diego Formation of southwestern San Diego County and northern Baja California Description: Pliocene fossil bird remains are particularly rich in the southern California area, with over 24 species being recovered from the San Diego Formation alone.

The first published record of any fossil bird from California was in 1901 for the species designated as Mancalla californiensis. The extinct flightless auks are represented by fossils of at least three species within the genus Mancalla in the San Diego Formation: Mancalla milleri, M. emlongi, and M. diegensis. These birds stood about a foot tall (30 centimeters.) The legs were short and slender as opposed to the chunky legs of penguins. Although these birds could not fly, they were adept as wing-propelled swimmers, with very flattened, paddle-like wing bones that helped push them through the water. Like other members of the family Alcidae, they would have “flown” underwater with wings outspread. Paleontologists also believe that the rigidity of the vertebrae may have helped them adapt to swimming. Birds in this genus were the most common bird of the San Diego Formation, with thousands of fossils being recovered. Ecology: Modern alcids are not flightless, but are diving birds that also use their powerful wings to swim.

They are found in the Northern Hemisphere, and include the murres, Atlantic puffins, razorbills, and guillemots. It is likely that, here in the Northern Hemisphere, the flightless auks occupied a similar ecological niche that the penguins fill in the Southern Hemisphere. They may have lived in large groups, much as modern penguins do today. Both alcids and penguins are extremely proficient divers; some alcids have been captured at depths of 180 meters (590 feet!) Scientists postulate that flightless birds most likely developed in conditions where there was an abundant and regular supply of food, and a lack of predators, or at least where predators were rarely encountered. These seemingly ideal conditions may have been present in San Diego’s Pliocene embayment. There was apparently an abundance of fish for these birds to feed on, and there may have been islets and islands off shore that allowed them to avoid the majority of large mammalian predators. These islands could have served as rookeries for young birds, also. Why would it be favorable for survival for a bird to lose the ability to fly? Large flight wing muscles and bones require much energy to maintain.

In a safe supportive environment, Mancalla and many other birds conserved energy by becoming flightless over time. The physical mechanism for this transformation to flightlessness involves the simple alteration of a few genes that control development, so that the adult bird has many features of the flightless young chick. Feathers became more open and less tightly constructed and the bird’s overall size tended to become larger, with a bigger pelvic region and hind legs. In many ways the adult flightless Mancalla would have looked like a large, overgrown chick. Another member of the Alcidae that has become extinct did so only during very recent times. The Great Auk, or Pinguinis impennis, a large black and white flightless seabird found in the north Atlantic, was often seen by fishermen offshore. Standing as tall as two feet (60 centimeters), these birds were slow and awkward on land. During its nesting period of a few weeks each summer the birds waddled onshore to lay their eggs in huge colonies on the islands off Greenland, Iceland, Labrador, Great Britain, and Europe.

Laying only a single egg and having little or no defense against human predation, the birds were slaughtered by the thousands by hunters and their eggs collected as well, with the sad result that they became extinct by 1844. Part of their vulnerability could be attributed to the fact that as large, plump birds they, and their large eggs, made more tempting targets for hunters than other smaller birds. Like modern penguins, their colonial nesting habits also put them at risk. Of Historical Interest Great Auk images figure in several prehistoric cave paintings in France and Spain. Suggested Reading Abbott, Patrick L. 1999. The Rise and Fall of San Diego. San Diego: Sunbelt Publications. Chandler, Robert M. 1990. Fossil Birds of the San Diego Formation. Ornithological Monographs No. 44. Washington, D.C. Feduccia, Alan. 1996. The Origin and Evolution of Birds. New Haven: Yale University Press. Olson, Storrs L. 1985. The fossil record of birds. In: Farner, D. S., King, J. R. and Parkes, K. C., eds., : Avian Biology Vol.

8. NY: Academic Press. Illustration: Doug Henderson Penguins | Basic Facts About Penguins | Defenders of Wildlife Penguins Basic Facts About Penguins Penguins are aquatic, flightless birds that are highly adapted to life in the water. Their distinct tuxedo-like appearance is called countershading, a form of camouflage that helps keep them safe in the water. Penguins do have wing-bones, though they are flipper-like and extremely suited to swimming. Penguins are found almost exclusively in the southern hemisphere, where they catch their food underwater and raise their young on land. © Joan Cambray Diet Staples: Krill, fish and squid. In general, penguins closer to the equator eat more fish and penguins closer to Antarctica eat more squid and krill. Population Did You Know? Larger penguin species are found in colder climates where their large body mass enables them to cope with the conditions, while smaller penguins inhabit warmer climes. The penguin species with the highest population is the Macaroni penguin with 11,654,000 pairs. The species with the lowest population is the endangered Galapagos penguin with between 6,000-15,000 individuals.

Range Penguins can be found on every continent in the Southern Hemisphere from the tropical Galapagos Islands (the Galapagos penguin) located near South America to Antarctica (the emperor penguin). Behavoir Penguins can spend up to 75% of their lives in the water. They do all of their hunting in the water. Their prey can be found within 60 feet of the surface, so penguins have no need to swim in deep water. They catch prey in their beaks and swallow them whole as they swim. Some species only leave the water for molting and breeding. Did You Know? The emperor penguin breeds in the coldest environment of any bird species; air temperatures may reach -40° (F/C), and wind speeds may reach 89 miles per hour (144 km/hr)! Penguins are social birds. Many species feed, swim and nest in groups. During the breeding season, some species form large groups, or “rookeries”, that include thousands of penguins. Each penguin has a distinct call, allowing individuals to find their mate and their chicks even in large groups. Reproduction Mating Season: Varies depending on the species, though most breed during spring and summer.

Incubation: Varies from 1 month-66 days depending on the species. Number of offspring: King and emperor penguins lay one egg. All other species of penguin lay two eggs. 'Wildlife of the Region' Wildlife No land-based vertebrate animals inhabit Antarctica. Invertebrates, especially mites and ticks, which can tolerate the lower temperatures, exist in the Antarctic Peninsula but are still considered rare. The surrounding ocean, however, abounds in living creatures. Large numbers of whales feed on the rich marine life, especially krill. Six species of seals (including the crabeater, elephant, and leopard) and about 12 species of birds live and breed in the Antarctic. The most prominent inhabitant of the Antarctic is the penguin. A flightless bird, it lives on the pack ice and in the oceans around Antarctica and breeds on the land or ice surfaces along the coast. Most typical are the Ad�lie and Emperor penguins. Humpback Whales Hump Back Whale The Hump Back Whale in its natural habitat provides a wonderful spectacle as it leaps from the water. A 15 Meter male can have flippers up to 5 meters long.

Whales are classified into two groups - toothed whales, such as dolphins and sperm whales, and baleen whales, such as blue or humpback. Baleen whales have baleen plates hanging from their upper jaws that allow them to filter plankton out of the tons of water they take into their mouths. Plankton, tiny organisms that live in water, are baleen whales' only food source. Penguins The emperor penguin - The largest of the penguins, lays its single egg during the coldest time of the year, when temperatures drop as low as -66 degrees C (-80 degrees F). The egg is incubated on top of the parent's feet, protected by abdominal folds of skin. Young chicks remain here for a short time until they are able to regulate their own body temperature. Penguin, common name for flightless, aquatic birds of the southern hemisphere. The name penguin originally was applied to the now extinct great auk of the North Atlantic, a large flightless, black and white bird with an upright stance. Similar flightless birds were discovered subsequently in the southern hemisphere, and they were also called penguins, a name that is now restricted exclusively to these birds.

Penguins usually walk or hop and toboggan along on their breasts, pushing with wings and feet. They swim with great speed and agility. The flippers are their sole means of propulsion; the feet are trailed behind or used in steering. Some species progress by porpoising, which is swimming underwater some distance, emerging in a graceful arc to take a fresh breath, and submerging again. Penguins feed on fish, cuttlefish, crustaceans, and other small sea animals. In captivity the king and emperor penguins normally do not learn to pick up their own food, and after they have been taught to feed by strenuous forced feeding they must be fed by hand each day. Penguins are gregarious birds and are found in flocks even at sea. On land the colonies often number in the hundreds of thousands. Although the birds have suffered greatly at the hands of humans, who have slaughtered great numbers for their blubber and, more recently, for their skins, the inaccessibility of the Antarctic region has helped preserve the group. Natural enemies of the penguin include leopard seals, killer whales, and, in the case of young chicks and eggs, skuas.

Penguin Rookery penguin | bird order | Britannica.com bird order rockhopper penguin Penguin (order Sphenisciformes), any of 18 species of flightless marine birds that live only in the Southern Hemisphere. The majority of the 18 species live not in Antarctica but rather between latitudes 45° and 60° S, where they breed on islands. A few penguins inhabit temperate regions, and one, the Galapagos penguin (Spheniscus mendiculus), lives at the Equator . Emperor penguins (Aptenodytes forsteri). Michael C.T. Smith—The National Audubon Society Collection/Photo Researchers General features The stocky, short-legged appearance of penguins has endeared them to people worldwide. They range from about 35 cm (14 inches) in height and approximately 1 kg (about 2 pounds) in weight, in the little blue , or fairy, penguin (Eudyptula minor) to 115 cm (45 inches) and 25 to 40 kg (55 to 90 pounds) in the emperor penguin (Aptenodytes forsteri).

Most are black on the back and white below, often with lines of black across the upper breast or spots of white on the head. Colour is rare, being limited to red or yellow irises of the eye in some species; red beaks or feet in a few; yellow brow tufts in the three species of Eudyptes; and orange and yellow on the head, neck, and breast in the emperor and king (A. patagonica) penguins. Magellanic penguins (Spheniscus magellanicus) on the coast of southern … Encyclopædia Britannica, Inc. Heads of representative sphenisciforms. Encyclopædia Britannica, Inc. The total populations of some species, such as the emperor, are estimated in the hundreds of thousands, but most species of smaller penguins certainly run into the millions. Immense island breeding colonies, some teeming with hundreds of thousands of nesting pairs, represent a large potential food resource, but the economic importance of penguins is negligible. Nineteenth-century whalers and seal hunters visited some colonies for meat and eggs, and a penguin oil industry once took large numbers of the birds.

By the early 20th century, however, this exploitation was no longer profitable, and most colonies were left alone or actively protected. Some species are now increasing in numbers, apparently as a result of the mid-20th century’s decimation of Antarctic whales, which compete with penguins for the krill (minute crustaceans) on which both feed. Penguin populations, however, are highly vulnerable to changes in climate and ocean temperature, including recent global warming . Penguins also are very sensitive to depletion of local fish populations by humans. Magellan penguins (Spheniscus magellanicus). Opium Wars Scientists have long wondered how penguins are able to find their way back to their colonies from far out at sea, where currents may have carried them great distances. Also perplexing is how they are able to direct themselves correctly on land in the absence of clear-cut landmarks. Studies of penguins transported to the interior of Antarctica have found that they are able to find their way back to the ocean by using the sun as a directional aid. It is probable that the same means of orientation is used at sea. Upon approaching the coast they are able to recognize features of the shoreline and ocean bottom.

Food habits The type of food utilized varies with the species, the geographic region, and the time of year. Most of the smaller southern penguins feed primarily upon krill , which attain high densities in the rich, well-oxygenated Antarctic waters. Cephalopods (squid and cuttlefish) and small fishes may form substantial fractions of the food, and in a few, such as the Cape penguin, fish is the basic element of the diet. The total weight of food consumed by a large penguin colony is prodigious, often exceeding several tons per day. Form and function The penguins are highly specialized for their flightless aquatic existence. The feet are located much farther back than those of other birds, with the result that the bird carries itself mostly upright; its walk can thus be described as plantigrade (i.e., on the soles). The sole comprises the whole foot instead of just the toes, as in other birds. The most notable characteristic of the group is the transformation of the forelimb into a paddle. This is accompanied by a body morphology particularly adapted to movement in a liquid medium.

The thoracic (rib) cage is well developed, and the sternum bears a pronounced keel for the attachment of the pectoral muscles, which move the flippers . The flipper has the same skeletal base as the wing of flying birds but with its elements shortened and flattened, producing a relatively rigid limb covered with very short feathers—an ideal organ for rapid propulsion. The body plumage likewise consists of very short feathers, which minimize friction and turbulence. The density of the plumage and the layer of air that it retains provide almost complete insulation of the body. Insulation of the bird’s body is particularly important for Antarctic species that live in water that is always below 0 °C (32 °F). The cooling power of seawater at −1.9 °C (28.6 °F) is equal to that of a temperature of −20 °C (−4 °F) with a wind of 110 km (70 miles) per hour. The skin is insulated by a layer of air trapped under the plumage, and the only bare skin in direct contact with the water is that of the feet. In the case of the emperor penguin on land, the feet are in almost constant contact with ice.

The skin temperature is in the neighbourhood of 0 °C, and snow does not melt upon contact. This is possible because of remarkable anatomical arrangements in the lower limb, whereby closely adjacent arteries and veins form a system of heat exchange between opposing flows of blood. This arrangement permits cooled blood from the feet to absorb heat from outflowing blood, providing maximum economy of heat consistent with the functioning of the foot. Like other seabirds, penguins have salt glands that enable them to ingest salt from seawater. Excess chloride is excreted in the form of a solution the concentration of which is greater than that of seawater. These glands are located above the eyes and are already functional in the young chick, which begins to consume food of marine origin from its first day of life. Recent research has shown that the species most isolated geographically, such as the emperor penguin , can be subject to diseases. Some, such as the Adélie penguin, carry in their bodies trace amounts of pollutants, albeit in lower quantities than are found in many birds that live closer to humans.

Evolution and classification Fossil record Evidence from paleontology indicates that the penguins and the order Procellariiformes (albatrosses, shearwaters, and petrels) had a common origin. Both groups are represented by well-defined fossils dating to about 50 million years ago. The flightless sphenisciform line produced a number of distinctive side branches, all recognizably penguins, some giant in size. All of the fossil remains of penguins have been collected within the zone of the present-day distribution of the Sphenisciformes. Some apparently lived in warmer regions than do most of today’s penguins. Phylogenetic analysis of living and fossil penguins shows that the group evolved a large body size early in its history. For example, two of the largest fossil penguins known— Icadyptes, which stood some 1.5 metres (about 5 feet) tall, and Anthropornis, which stood about 1.8 metres (6 feet) tall—date to the Eocene Epoch (56 million to 33.9 million years ago). Living penguins make up a separate lineage characterized by smaller, highly aquatic species that began about 8 million years ago.

The comparatively small size of living penguins is thus a geologically recent phenomenon that postdates the original radiation of giant penguins. Classification Order Sphenisciformes (penguins) 18 species in 1 family (Spheniscidae) with 6 genera found in oceans of the Southern Hemisphere; wings flipperlike for propulsion underwater; webbed feet short and stout; stance upright; feathers short and dense, molted in patches; length 35–115 cm (14–45 inches); fossil forms to 180 cm (70 inches). Genus Eudyptes ( crested penguins) penguin - Student Encyclopedia (Ages 11 and up) Seen from a distance, a colony of penguins might easily be taken for a group of little men. These sea birds stand erect and flat-footed and are often drawn up in long regular files like soldiers. They walk with a tread so stately and dignified that the sight is very comical. In the species known as the king penguin, the resemblance to man is heightened by the grayish-blue coat on the back.

This is set off by black plumage on the head, a white breast, and a yellow "cravat" at the throat. Article Contributors How Do Penguins Protect Themselves from Enemies? | Sciencing How Do Penguins Protect Themselves from Enemies? By Jonathan Marker Tom Brakefield/Stockbyte/Getty Images From the Galapagos Islands to Antarctica, penguins encounter threats from predatory birds, marine mammals and sharks. Whether on land or in the sea, penguins employ a number of defense mechanisms against their enemies. These include the sheer number of penguins in a colony, burst swimming speed, high maneuverability in the water and swift exits from the sea. Strength in Numbers The 17 species of penguins persist almost exclusively in the coastal Southern Hemisphere, with ranges including Antarctica, South America, Australia, New Zealand and South Africa. The exception is the Galapagos penguin, which is the only species that lives north of the equator. Regardless of geographic location, the tendency of most penguins to live in large colonies offers the protection of sheer numbers against enemies in the air, on land and under the waves, if only by providing a warning to other penguins that an enemy is nearby.

Huddling together also discourages straggling from the colony and denies predators what would otherwise be an easy meal. Penguin Camouflage The distinct black and white coloring of penguins is a type of camouflage called countershading, which helps penguins hide from predators and hunt prey. The countershading observed in penguins generally consists of black feathers distributed atop their heads, backs and flippers to help them blend in with the darkness of the ocean when viewed from above. Their bellies and undersides are colored white to blend in with the bright surface of the ocean when viewed from below. Protection on Land Depending on geographic location, on land penguins generally face the threat of predation by wild dogs, feral cats, rats and predatory birds like Arctic skuas and raptors. Although penguins walk slowly with a distinctive waddle and cannot fly away from danger, they can slide on their bellies in a maneuver called "tobogganing" to flee their foes. When at the ocean's edge, tobogganing can allow penguins to make a quick escape into the water, where they maneuver best. In addition, penguins' ability to live in cold, inhospitable environments is itself a protection against predators.

Perhaps most famously, emperor penguins avoid land predators by breeding inland on the Antarctic continent, an environment too hostile for any land predators. Their physical and behavioral adaptations to the cold are evolved precisely for this reason. Protection at Sea Penguins spend most of their lives in water and are exposed to a wide variety of marine predators, including sharks and large marine mammals like orcas and leopard seals. Porpoising is a technique that penguins can use to jump out of the water at high speed; when close to land, this technique can allow the penguin to escape from a marine predator and return to the safety of the colony. Additionally, although penguins can achieve speeds of up to 22 miles per hour, marine predators like orcas are faster. To compensate, penguins use sharp, zigzagging turns to outmaneuver these larger and less agile animals. References

Question: Which flightless marine birds of the southern hemisphere live in rookeries?
Answer: Penguins